Electromagnetic relay with conductive core and conductive housing



Jan. 21, 1964 r R. NITSCH ELECTROMAGNETIC RELAY WITH CONDUCTIVE CORE AND CONDUCTIVE HOUSING Filed March 26, 1962 Fig.2

Fig.3

United States Patent 3,118,988 ELEtITROMAGNETIC RELAY WITH CONDUCTEVE CORE AND CONDUCTIV'E HOUSING Rndolt' Nitsch, Munich, Germany, assignor to Siemens &

Haislre Aktiengeseilschaft Berlin and Munich, a corporation of Germany Filed Mar. 26, 1962, er. No. 183,335 Claims priority, application Germany Mar. 29, 1961 Claims. (Cl. 200-87) The invention disclosed herein is concerned with an electro-magnetic relay comprising a sealed housing, made at least in part of metal, for accommodating the armature. The metallic housing of a known relay of this kind contains elaborate contact devices, controlled by the armature, which render the construction complicated and greatly affect the spatial requirements thereof.

The object of the invention is to provide a relay of this kind which is of simple construction and requires relatively little space.

This object is achieved by utilizing the housing so as to serve as a relay contact, thereby reducing the expenditure for the required contact means. Particular advantages are achieved upon constructing the housing, which receives the armature, in hermetically sealed manner, thereby reducing the number of lead-through means for establishing connections with the contact devices and therewith also reducing the number of points at which leaks can appear.

The expenditure, so far as contact devices are concerned, can be further reduced by utilizing the armature as electrical conductor. This is particularly true upon utilizing as a magnetic conductor at least one contact element which is disposed in insulated manner in a wall of the housing.

An electrically conductive connection between the armature and the housing can be effected in simple manner by journal-ling at a wall of the housing the armature, which is, for example, made in the form of a resilient lamella. It is, however, likewise possible to journal the armature by means of a spring which is fastened to a housing wall.

The relay according to the present invention can be constructed with only one contact element arranged in insulated relation with respect to a housing Wall and serving at the same time as a magnetic conductor, so that the number of lead-through means, extending into the interior of the housing, is reduced to the least possible number, namely, to one. A relay having only one make contact may be constructed by the provision of an armature which establishes in its operative working position an electrically conductive connection between the housing and a contact element disposed in insulated relation with respect thereto. It is, however, also possible to equip a relay, constructed in accordance with the invention, with one make contact and one break contact, with the aid of a single lead-through extending into the enclosed space.

This may be achieved by constructing the housing of two mutually insulated parts, whereby a contact element is disposed in cooperative relation with a first housing part, which element also serves as a magnetic conductor, the armature establishing in one of its end positions a connection between the first housing part and the contact element, while electrically connecting the two housing parts in its second end position. The armature can be journalled, for example, in the first housing part.

The part of the housing wall which cooperates with the armature can be provided with suitably formed stop means .for the armature, which may be constructed, for example, by indenting the corresponding housing wall so as to form a boss.

3,118,988 Patented Jan. 21, 19-64 Further details of the invention will be described with reference to the accompanying drawing showing embodiments of relays having an armature which also serves as an electrical conductor.

FIG. 1 shows in cross-sectional representation a relay With a make contact; and

FIGS. 2 and 3 show in similar representation relays provided respectively with a break-make contact.

The relay represented in FIG. 1 comprises two metallic housing parts 1 and 2, made, for example, of iron, forming an enclosed space for the armature 5. In the housing part 1 is provided a pin-like contact element 4 which is fused thereto by a glass seal 3 and serves also as a magnetic conductor. The armature 5 which also serves as an electrical conductor is journaled at the housing part 2 by means of a spring 6. The pin 4, serving as a core, carries a magnetizing winding 7. The angular metal sheet 8 provides for a flux return path respectively from the armature and housing, to the core pin 4.

Upon energization of the Winding 7, the armature 5 will be attracted by the pin-like core 4 and will thus establish electrical connection with the pin 4 which is disposed in insulated relation with respect to the housing. An electrical connection between the armature 5 and the housing part 2 in provided by the spring 6. It is, however, possible to modify the arrangement so that the armature 5 engages the housing part 1 instead of engaging the pin 4, thus interconnecting the two housing parts electrically. The structure according to FIG. 1 operates as a make contact.

Parts shown in FIGS. 2 and 3 which correspond to parts shown in FIG. 1, are indicated by like reference numerals.

In FIG. 2, there is provided an intermediate member 14), connected with the housing part 1, upon which is disposed at second metallic housing part 9. The electrically conductive armature .11 is journalled on the housing part 1 by means of a spring 12. In its illustrated position, the armature 11 engages a boss 13 formed by an indentation of the housing part 9, thereby forming a stop for contact engagement by the armature in the normal position thereof, thus producing an electrically conductive connection between the housing parts 9 and 1. Upon energization of the magnetizing winding 7, the armature 11 will be attracted by the core pin 4. The electrical connection between the housing parts 9 and l is thus interrupted, and connection is established between the housing part '1 and the core pin 4. The contact actuation therefore con-forms to that of a break contact.

In the arrangement according to FIG. 3, a metallic housing part 14 is directly connected With the housing part 1, an electrically conductive pin 15 being fused to the part 14 by a glass seal 18. The armature 16 is journalled on the housing part 14 by means of a spring 17. In the illustrated position of the armature 16 there is an electrical connection between the pin 15 and the housing. This connection is interrupted upon energization of the magnetizing Winding 7 and consequent alteration of the armature 16 while a connection is established between the core pin 4 and the armature 16, and therefore with the housing. The structure operates in the nature of a breakmake contact.

Electrical connections to the energizing coil 7 and the contact parts may be provided in suitable known manner.

Changes may be made within the scope and spirit of the appended claims which define what is believed to be new and desired to have protected by Letters Patent.

I claim:

1. An electromagnetic relay, comprising means forming a sealed housing having a metallic electrically conductive wall, an elongated magnetically and electrically conductive member rigidly mounted adjacent one end of one wall of said housing in insulated relation thereto and extending therefrom, said member forming the magnet core of said relay with the adjacent end extending through the housing wall, an energizing winding encircling said core for magnetizing the latter responsive to current flowing through such winding, an elongated armature made of magnetizable and electrically conductive material, an

elongated spring for movably mounting said armature within said housing in electrically conductive relation with said metallic wall thereof, said spring being operative to support said armature for movement from a normal position into engagement with said core member responsive to flux created by said core member upon energization of said energizing winding, whereby said housing is utilized as a part of the contact means of said relay, and magnetically conductive means operatively extending from said housing to the .free end of said core member, forming a flux return path from the armature and housing to said core member.

2. An electromagnetic relay, comprising means forming a housing having a first and a second wall, an insulating member interposed between said first and said second wall, a magnetically and electrically conductive member mounted on said first wall in insulated relation with respect thereto and extending therefrom, said member forming the magnet core of said relay, an energizing winding cooperatively disposed with respect to said core for magnetizing the latter responsive to current flowing 9 through such winding, an armature, made of magnet1zable and electrically conductive material, spring means mounting said armature within said housing in electrically conductive relation with said first wall, with said armature operative to move from a normal position into engagement with said core member responsive to flux created by said core member upon energization of said energizing winding, and a boss formed on said second wall for engagement with said armature in the normal position thereof, whereby said second wall is in normal position of said armature electrically interconnected with said first wall, with said housing being utilized as part of the contact means of said relay.

3. An electromagnetic relay, comprising means forming a sealed housing, a magnetically and electrically conductive member mounted on a first wall of said housing in insulated relation thereto and extending therefrom, said member forming the magnet core of said relay, an energizing winding cooperatively disposed with respect to said core for magnetizing the latter responsive to current flowing through such winding, an armature, made of magnetizable and electrically conductive material, spring means movably mounting said armature within said housing on said second wall in electrically conductive relation therewith, with said armature operating to move from a normal position into engagement with said core member responsive to flux created by said core member upon energization of said energizing winding, whereby said housing is utilized as part of the contact means of said relay, and a conductor carried by said second housing wall in insulated relation with respect thereto, said armature being normally in engagement with said conductor.

4. An electromagnetic relay comprising a plurality of parts forming a closed housing having a first and a second housing part made at least partially of metal, insulating parts disposed between the first and the second housing part and separating said housing parts electrically, a magnet core, made in the form of a pin of magnetizable and electrically conductive material, mounted in the first housing part in electrically insulated relation with respect thereto, one pole of the pin-like core extending into the housing and the remaining part thereof projecting from the housing, a magnetizing winding mounted on the portion of the magnet core projecting from the housing for magnetizing the core, a magnetizable and electrically conductive armature disposed within the housing, means forming a stop arranged at the second housing part for cooperation with said armature, spring means fastened to the first housing part, said armature being supported by said spring means and electrically conductively connected thereby with the first housing part and establishing in its normal position, by contact with the stop, an electrical connection between the first and the second housing part, said armature being attracted by the magnet core upon energization of the energizing winding, whereby such electrical connection is opened and an electrical connection is established between the magnet core and the first housing part, and terminal elements, disposed exteriorly of the housing, for the electrical connection of the magnet core, and the first and second housing parts.

5. An electromagnetic relay comprising, a plurality of parts forming a closed housing having a first and a second housing part made at least partially of metal, a pinlike magnet core made of magnetizable and electrically conductive material and fastened in the first housing part in electrically insulated relation with respect thereto, one of the ends of said magnet core projecting into the closed housing and the remaining part thereof projecting from the housing, a magnetizing winding disposed exteriorly of the housing and mounted upon the part of the pin-like core projecting from the housing and being operative upon energization thereof to magnetize said core, a contact element connected with the second housing part in electrically insulated relation with respect thereto, part of said contact element projecting into the housing and the remaining part thereof extending from the housing to provide a terminal therefor, an armature made of magnetizable and electrically conductive material, spring means within the housing connected with said armature and one housing part, and electrically connecting said armature with the housing, said armature establishing in its normal position, by engagement with the contact element, an electrical connection between said contact element and the housing, and being upon energization of the magnetizing winding attracted by the magnet core, Whereby the electrical connection is interrupted and an electrical connection is established between the housing and the magnet core, and terminal elements, disposed exteriorly of the housing, for the electrical connection of the magnet core and the contact element and the housing, respectively.

References Cited in the file of this patent UNITED STATES PATENTS 1,375,983 Thomson Apr. 26, 1921 2,103,929 Bear Dec. 218, 1937 2,848,661 Amourig Aug. 19, 1958 

1. AN ELECTROMAGNETIC RELAY, COMPRISING MEANS FORMING A SEALED HOUSING HAVING A METALLIC ELECTRICALLY CONDUCTIVE WALL, AN ELONGATED MAGNETICALLY AND ELECTRICALLY CONDUCTIVE MEMBER RIGIDLY MOUNTED ADJACENT ONE END OF ONE WALL OF SAID HOUSING IN INSULATED RELATION THERETO AND EXTENDING THEREFROM, SAID MEMBER FORMING THE MAGNET CORE OF SAID RELAY WITH THE ADJACENT END EXTENDING THROUGH THE HOUSING WALL, AN ENERGIZING WINDING ENCIRCLING SAID CORE FOR MAGNETIZING THE LATTER RESPONSIVE TO CURRENT FLOWING THROUGH SUCH WINDING, AN ELONGATED ARMATURE MADE OF MAGNETIZABLE AND ELECTRICALLY CONDUCTIVE MATERIAL, AN ELONGATED SPRING FOR MOVABLY MOUNTING SAID ARMATURE WITHIN SAID HOUSING IN ELECTRICALLY CONDUCTIVE RELATION WITH SAID METALLIC WALL THEREOF, SAID SPRING BEING OPERATIVE TO SUPPORT SAID ARMATURE FOR MOVEMENT FROM A NORMAL POSITION INTO ENGAGEMENT WITH SAID CORE MEMBER RESPONSIVE TO FLUX CREATED BY SAID CORE MEMBER UPON ENERGIZATION OF SAID ENERGIZING WINDING, WHEREBY SAID HOUSING IS UTILIZED AS A PART OF THE CONTACT MEANS OF SAID RELAY, AND MAGNETICALLY CONDUCTIVE MEANS OPERATIVELY EXTENDING FROM SAID HOUSING TO THE FREE END OF SAID CORE MEMBER, FORMING A FLUX RETURN PATH FROM THE ARMATURE AND HOUSING TO SAID CORE MEMBER. 